Michael Sims’s stroll through the world of the great and peculiar American literary giant Henry David Thoreau is personal and idiosyncratic and goes its own way – rather like Thoreau himself. In his new biography, The Adventures of Henry Thoreau, Sims (who wrote about E.B. White in his 2011 book “The Story of Charlotte’s Web”), takes up whatever he’s interested in and doesn’t worry about thoroughness.

(Thoreau, by the way, was the first writer to make puns about his name.)

“I’m more interested in Thoreau’s imaginative response to nature, for example, than in his role as social critic and moral gadfly, and consequently much of this book takes place outdoors,” explains Sims.

So Sims lets himself meander after American literature’s best meanderer. And wherever Sims stops for a spell, he’s engaged and engaging. He shows us, for example, Thoreau in the midst of composing: “He was discovering that he enjoyed using an outdoor ramble as a unifying cord on which to string his thoughts.”

Sims reminds us, though he doesn’t quote them often enough, that the best biographical material of all is Thoreau’s own journals: “At the time of his death [in 1862], he had written two million words in this private storehouse, filling seven thousand pages in forty-seven volumes between October 1837 and November 1861. He came to realize that his most important task was attending to the natural phenomena of everyday life, and at one point he half-jokingly complained that his observations were becoming more scientific and less poetic.” The journals reveal the man not because of Thoreau’s desire to reveal himself but because they record what Thoreau actually noticed and thought: “He needed the journal for talking with himself. He kept reminding himself to pay attention, to look more closely at fleeting life.”

Thoreau is so good at evoking the immediate natural world. But Sims is at his best when he’s writing about the topics that hamstrung Thoreau – topics such as friendship and romance.

Thoreau was a genius at conveying this and creating our appreciation of animals, trees, stones, and the air but not at characterizing people or accounting for relationships. Even as a child, Sims tells us, “Young Henry was not adept at interpreting facial expressions.”

At Harvard, a roommate witnessed Thoreau’s “tendency to notice animals more than people.” He had trouble reading grown-ups, though as Sims shows, Thoreau had a knack for teaching children. He took them seriously and yet could be his somewhat goofy self with them. He wasn’t shy or compromised as he often seems to have been when in the presence of adults.

Like a documentary filmmaker, Sims sometimes spends entire (short) chapters focused on other people and events in Concord, Mass., and I would object except that he handles them so excellently. He sketches, for example, the family life of Thoreau’s mentor Ralph Waldo Emerson and the routines and struggles of, among others, Thoreau’s acquaintance, author Nathaniel Hawthorne.

Sims’s recounting of the death of Thoreau’s brother, John, and Thoreau’s grief at that time is more touching than any other biographical account I’ve read: “Soon after John’s funeral, Henry’s calm self-possession began to collapse. He sat staring into space, doing nothing, saying nothing.... [His sisters] Sophia and Helen tried to help Henry, who seemed to be steadily declining. They led him outdoors to try to interest him in nature, but to no avail.”

Sims seems fond of Thoreau in the way Thoreau’s friends and family were fond of him. They saw his peculiarities and – while not admiring them – loved him anyway.

In some ways, it’s easier to say what “The Adventures of Henry Thoreau” is not than what it is. That is, it is not a complete or “new” biography. It’s not a study of “Walden.” And it’s not academic, argumentative, or quirky (like Robert Sullivan’s entertaining “The Thoreau You Don’t Know”). Instead, it’s the odd book about a renowned author that’s actually affectionate.

“After he had got used to skates again each winter, Henry would soon recklessly race down even a foot-wide strip of ice between shore and water. He loved the freedom to follow the windings of a stream. He would whisper along on his skates, and be surprised to reach a particular bend in the river or a tributary brook sooner than expected.... He felt as if he had winged feet, like Hermes.”

Sims doesn’t try to remake Thoreau. He just shows us how to enjoy him.

Bob Blaisdell edited Thoreau: A Book of Quotations; he is editing an anthology of writings and speeches on Civil Obedience for Dover Publications.